1. Field
The disclosed subject matter relates to a catheter for a coronary artery for treating and imaging the heart or a peripheral tissue of the heart and an engaging method for the catheter.
2. Description of the Related Art
Conventionally, catheters for imaging a coronary artery, catheters of the Judkins type, the Amplatz type and so forth. Usually, these types of catheters are introduced from a femoral artery by the Seldinger method or a sheathing method to selectively image a coronary artery.
Also, many different treatments for a peripheral region of the heart using a catheter are available at present. For example, percutaneous transluminal coronary angioplasty (PTCA) of ischemic heart disease treatment using a catheter with a balloon is available. With regard to this treatment, in order to insert a treatment catheter into a target blood vessel safely and efficiently, the performance of the treatment catheter is important, and a guiding catheter which softens a reaction caused by the insertion and provides sufficient backup force to assist smooth introduction is often required. Shapes of such a guiding catheter can be similar to those of the Judkins type, the Amplatz type and so forth which are similarly available as in the case of the imaging catheter for a coronary artery described above. Usually, a catheter having any of the above noted shapes is introduced from a femoral artery by the Seldinger method or the sheathing method to selectively assure introduction into a coronary artery, and then a treatment catheter such as a balloon catheter for PTCA is introduced into the inner face of the guiding catheter.
In the imaging or treatment processes for such conventional catheters, since the introduction site is a femoral region, in order to stanch a penetration site after the surgery, complete bed rest may be required. Accordingly, urination, defecation, and eating and drinking may be required to be carried out in a supine position, and there is a problem in that discomfort, such as discomfort associated with lumbago may be experienced by the patient. Further, where a catheter is introduced from a femoral region, there is the possibility that, even if the patient is in complete bed rest, bleeding may occur, and there is a problem in that such bleeding may reach the retroperitoneum and cause further complications. Also urination may be difficult when a patient is in a supine position, and in this instance, there is a problem that, through use of a urethral catheter, there is the possibility that a urinary tract infection may occur.
As a method for eliminating or preventing the problems described above, introduction of the catheter from an artery of an arm, particularly from a brachial artery or a radial artery, is considered effective. In particular, even when keeping a state in which a brachial penetrated site is stretched, the patent can walk immediately after the surgery, and urination, defecation, and eating and drinking can be carried out in an ordinary manner without lumbago and so forth. Further, the possibility of bleeding from the retroperitoneum and/or the contraction of a urinary tract infection can be prevented.
In view of such circumstances as described above, Japanese Patent No. 3,563,540 (hereinafter referred to as Patent Document 1) discloses a catheter for the left coronary artery having a shape suitable for introduction from an arm. FIG. 8 shows the catheter for the left coronary artery disclosed in Patent Document 1. Referring to FIG. 8, the catheter 100 for the left coronary artery includes a catheter main body 112 and a hub 114. The catheter main body 112 is configured from a substantially linear main body portion 116 and a distal end portion 118 having a curved shape. The distal end portion 118 is configured from a first substantially linear portion 122 continuing from the main body portion 116 through a first curved portion 120, a second substantially linear portion 124 continuing from the first substantially linear portion 122 through a second curved portion 123 curved in the opposite direction to that of the first curved portion 120, a third substantially linear portion 126 continuing from the second linear portion 124 through a third curved portion 125 curved in the same direction as that of the second curved portion 123, and a substantially linear extreme distal end portion 130 continuing from the third substantially linear portion 126 through a fourth curved portion 128 curved in the same direction as that of the third curved portion 125. The catheter 100 for the left coronary artery is shaped such that, when the distal end of the catheter 100 is positioned in the opening of the left coronary artery, the first curved portion 120 is introduced from the brachiocephalic artery into the aortic arch. The catheter 100 for the left coronary artery is shaped such that the second substantially linear portion 124 can contact with a wall of the aortic arch on an opposite side with respect to the opening of the left coronary artery.
Since the catheter 100 for the left coronary artery has a configuration as described above, it can be introduced from the artery of an arm, for example, from the brachial artery or the radial artery into the opening of the coronary artery without passing the femoral artery. As a result, the catheter can be introduced easily, reliably and quickly and the burden after surgery on the patient can be reduced.